1. Field of the Invention
The invention relates to an ostomy appliance for attachment to the body and for collecting bodily waste.
Ostomy appliances are usually in the form of a bag for receiving the waste, the bag being connected to an adhesive wafer that can be attached to the skin of the patient. The wafer is typically in the form of a backing layer coated on the skin-facing surface with an adhesive layer and the wafer is provided with an aperture for accommodating the body opening. The size and shape of said aperture can often be adapted individually to fit the anatomy of the patient.
One of the crucial parts of such devices is the adhesive wafer. The wafer should be able to fit leak proof around the body opening, have good adherence to the skin without unintended detachment from the skin, but at the same time be easy to remove again without damaging the skin. Furthermore, the wafer should be able to follow the movements of the body and be comfortable to wear.
Pressure sensitive adhesives have for a long time been used for attaching medical devices, such as ostomy appliances, dressings (including wound dressings), wound drainage bandages, fistula drainage devices, devices for collecting urine, orthoses and prostheses to the skin. Hydrocolloid adhesives, in particular, are used for ostomy appliances.
The hydrocolloid adhesives contain hydrophilic particles or absorbents, which absorb moisture into the adhesive bulk and transmit moisture when conditions are saturated. However, the retention of moisture in hydrocolloid adhesives may cause changes in the adhesive, such as swelling, loss of cohesion and disintegration.
Due to the delicate nature of skin, there is a narrow window where a pressure sensitive adhesive can function as a good, skin friendly adhesive: On one hand, the adhesive should be able to provide a strong and secure attachment of the medical device to the skin, thus avoiding leakage and unintentional detachment of the device, but on the other hand, removal of the medical device from the skin should be painless and not cause damage to the skin.
Conventional pressure sensitive adhesives for collecting devices are usually based on adhesives that flow into the skin. This makes the adhesive very sticky to the skin, but also means that when the adhesive is removed; part of the top layer of the skin or epidermis is peeled off, a phenomenon known as skin stripping.
2. Description of the Related Art
WO 94/15562 and U.S. Pat. No. 5051259 disclose adhesive wafers wherein the skin-facing surface comprises at least two different adhesives. The adhesives are preferably hydrocolloid adhesives of different cohesion.
Thus, there is still a need for an ostomy appliance with reduced skin stripping but yet capable of secure attachment to the skin.